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    <title>Sentinel Toolbox Help - Statistics</title>
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<table class="header">
    <tr class="header">
        <td class="header">&nbsp;
            Statistics
        </td>
        <td class="header" align="right"><a href="../general/overview/SnapOverview.html"><img src="../images/snap_header.jpg"
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</table>

<h3>Statistics Display</h3>

<p>This dialog, opened via <img src="images/icons/Statistics24.gif">, displays statistical information about the currently
    selected band. See the screenshot for an example.
</p>

<blockquote>
    <img src="images/StatisticsDialog.png">
</blockquote>

The set of statistical information displayed comprises:
<ul>
    <li>the total number of pixels</li>
    <li>the minimum/maximum geophysical value</li>
    <li>the arithmetic mean of the geophysical values (see http://en.wikipedia.org/wiki/Arithmetic_mean)</li>
    <li>the standard deviation (sigma) (see http://en.wikipedia.org/wiki/Standard_deviation#With_sample_standard_deviation)</li>
    <li>the median of the geophysical values (see http://en.wikipedia.org/wiki/Median)</li>
    <li>several percentile thresholds (see http://en.wikipedia.org/wiki/Percentile)</li>
</ul>

<p>
    Additionally, two diagrams are displayed: the left one is a histogram, the right one shows the thresholds for all
    percentiles.<br>
    The statistics can be computed for a whole band, or the considered pixels can be restricted to those matching a
    single or multiple ROI masks. The list of masks can be narrowed down by typing a pattern into the text field. For
    convenience, there is also the <img src="images/icons/MaskManager24.png">-icon which allows the user to open the
    <a href="MaskManagement.html">Mask Manager</a> tool window.
</p>

<p>
    The section "Statistical accuracy" allows the user to specify the accuracy with which the histogram shall be
    computed.
    Higher numbers indicate a higher accuracy but may lead to a considerably longer computation time.
    More precisely, this parameter determines the number of bin cells used for computing the histogram: the number of
    bin cells is computed by <b>10^a</b> with <b>a</b> the parameter.
    As the median and the percentile thresholds are derived from the histogram, the accuracy also influences these
    measures.
    The parameter value must be between 0 (histogram with one single bin) and 6 (histogram with 1,000,000 bins).
    When auto accuracy is enabled, the accuracy is set to 3.
</p>

<p>
    The export button below allows to export the statistics as CSV file. In case the statistics have been
    computed for ROI mask(s) which come from a shapefile, they also can be export to this original shapefile, thus
    enrich that shapefile by the statistical information.
</p>

<p class="inote"><b>Note:</b> A mouse right-click within the statistics tables
    brings up a context menu with the item <i>Copy data to clipboard</i>.
    This will copy the diagram data as tabulated text to the system clipboard.
    The copied text can then be pasted directly into a spreadsheet application
    (e.g. Microsoft&reg; Excel).
</p>

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